let str:string='我是字符串'
let num:number=21312321
let arr:Array<string|number|boolean>=['1','2','3',4,true]
let ars:number[]=[1,2,3,45,5]
let art:[number,string,boolean,null]=[1,'4',true,null]
console.log(str,num,arr,ars,art);

enum dircth{
    red,
    blue,
    black,
    white
}
console.log(dircth.red);

let flag:boolean=true
let never:unknown;
if(flag){
   
}